1. Field of the Invention
This invention relates to novel fire retardant polymer compositions containing ABS or urethane polymers and 2,2',3,3',4,4',5,5',7,7,7',7'-dodecachloro1,1',2,2',5,5',6,6'-octahydro-2, 2',5,5'-methanobiphenyl, with or without antimony compounds, and to methods for rendering polymeric materials containing said polymers flame resistant. For convenience, the flame retardant shall be referred to as RIS.
2. Description of the Prior Art
The increased use of polymeric materials, particularly in the building industry, has resulted in increased interest in rendering these materials fire retardant or flameproof. Presently, most commercially available plastics do not possess satisfactory fire retardancy and this inadequacy represents one of the major obstacles to the use of these materials.
The widely accepted fire retardant chemicals now in use with polymeric materials are antimony tri-oxide and organohalogen compounds. Of the organohalogen compounds, the best known are chlorendic anhydride (1,4,5,6,7,7-hexachlorobicyclo[2.2.1]-hept-5-ene-2,3-dicarboxylic anhydride); tetrabromo- or tetrachlorophthalic acid; 1,4'-isopropylidenebis(2,6-dichlorophenol) [tetrachlorobisphenol A] or the corresponding bromine-containing compound; "Chloran" (trademark), i.e., 2,3-dicarboxyl-5,8-endomethylene-5,6,7,8,9,9-hexachloro-1,2,3,4,4a,5,8,8a- octahydronaphthalene anhydride; chlorinated paraffins; and cycloaliphatic chlorine compounds such as the Dechloranes.
These organohalogen compounds have only limited utility in polymer compositions due to a number of disadvantages. For example, when such halogen compounds are incorporated into a polymer, various physical properties of the polymer are modified, e.g., change in melt viscosity, which requires higher processing temperatures, decrease in light stability, decrease in thermal stability, increase in density, adverse effects on heat distortion temperature, etc.
U.S. Pat. No. 3,313,763 discloses the use of RIS as a flame retardant for various polymeric compositions which have "enhanced physical properties such as heat distortion temperature over the properties of the base resin." The polymeric materials mentioned "are the homopolymers and copolymers of unsaturated aliphatic, alicyclic and aromatic hydrocarbons made from such monomers as ethylene, propylene, butene, pentene, hexene, heptene, octene, 2-methylpropene-1, 3-methylbutene-1, 4-methylpentene-1, 4-methylhexene-1, 5-methylhexene-1, bicyclo-(2.2.1)-2-heptene, butadiene, pentadiene, hexadiene, isoprene,2,3-dimethylbutadiene-1,3,2-methylpentadiene-1,3, 4-vinylcyclohexene, vinylcyclohexene, cyclopentadiene, styrene and methylstyrene and the like". There is no mention in this patent of the use of RIS in ABS or urethane polymers -- the subject matter of this invention.